Various benzothiazepines, useful intermediates or pharmaceuticals, and procedures to prepare them, are known. See e.g., Krapcho, U.S. Pat. No. 3,410,166 (Sept. 10, 1968); Kugita et al., U.S. Pat. No. 3,562,257 (Feb. 9, 1971); Igarashi et al., U.S. Pat. No. 4,552,695 (Nov. 12, 1985); Kugita et al., Chem. Pharm. Bull., 18(10), 2028-37 (1970); Takeda et al., U.S. Pat. No. 4,567,175 (Jan. 28, 1986); Mohacsi et al., U.S. Pat. No. 4,808,580 (Feb. 28, 1989); Floyd et al., U.S. Pat. No. 4,902,684 (Feb. 20, 1990).
Basu et al., Synth. Commun. 19(3 and $), 627-31 (1989), reports on a mild and selective method of ester hydrolysis. This method employs Dowex-50 resin.
Further benzothiazepines, e.g., cyano-containing-3-oxybenzothiazepines, and so forth, and procedures to prepare them, are lacking. Such would be highly significant and are needed. The otherwise reactable cyano moiety on such a product may be viewed as an obstacle to its provision.